In present-day vehicles, a hot topic is the fuel consumption reduction. A well known system is the stop and start device, that stops the engine when the car is stopped at a traffic light, or the regenerative braking, that converts braking mechanical energy to electric energy. However, the simplicity of current electrical generation and distribution system in a car, using a single alternator and a single energy storage element (the battery) both connected to a single powernet, severely limits the possibilities to optimize the energy consumption. In accordance with one non-limiting aspect of the present invention, multiple generation (i.e. solar panel . . . ) and storage elements (i.e. ultracapacitors, second batteries . . . ) are used to provide a broad range of options opens to manage and optimize energy flow. This may be accomplished with a complete system interconnection and control that is optimized to achieve the best energy use benefit.